It wasn't quite the wonderful world of Disney. At early screenings of Finding Nemo, Mouse House minions subjected the audience to inspection by metal detectors and surveillance with night-vision goggles. The idea was to keep would-be pirates from recording the flick. Yet within two days of Nemo's opening, high-quality copies were merrily being swapped via BitTorrent, the latest darling of the P2P set - and the new scourge of the MPAA.

Disney/PixarRip-off tide: Nemo was quickly pirated.

Originally created by Bram Cohen for sharing open source software, BitTorrent has found unexpected fans among video pirates, who appreciate the speed at which it handles large files, like 90-minute Hollywood features.

The key to its success: swarming downloads. Large files are broken into small pieces, so peers can download parts of a file while uploading others. BitTorrent eliminates leeches - those who take but don't give back - by fixing download rates to upload rates. The enforced reciprocity means bandwidth expands to handle the size of the swarm, preventing clogs.

As a piracy technology, though, BitTorrent is imperfect. It relies on trackers, or dedicated servers, to coordinate the swarm. This centralized structure is vulnerable to Napster-like legal attacks from the RIAA or MPAA. That vulnerability is being tackled by Overnet, another P2P network, which has borrowed BitTorrent's transfer method and replaced the trackers with a distributed search system. That leaves no legal target but the users themselves.

So far, the MPAA is playing it cool. A spokesperson insists the industry can stifle theft by going after traders through their ISPs. They may catch a few, but P2P users know there are always more fish in the sea.